Container construction



July 30, 1968 w. a. FRANKLIN, JR 3,394,637

CONTAINER CONSTRUCTION v Filed Dec. 27. 1965 IN VEN TOR. @K1/@5 lsv/0MM, M

6M Fa/awa United States Patent O 3,394,637 CNTAINER CGNSTRUCTION Walter B. Franklin, Jr., Bouider, Colo., assignor to Packaging Corporation of America, Evanston, Ill., a corporation of Delaware Filed Dec. 27, 1965, Ser. No. 516,549 3 Claims. (Cl. 93-56) ABSTRACT F THE DISCLOSURE A method of forming a collapsed tubular member from a sheet of foldable material. The collapsed tubular member is adapted to be eventually set up to form a container construction. The blank is provided with a pair of narrow rectangular wall-forming panels and a pair of wide rectangular wall-forming panels which are alternately arranged and foldably interconnected to one another. Narrow and wide closure aps are foldably connected to opposite ends of the respective wall-forming panels and an adhesive coating is applied to alternate surfaces of the closure flaps connected to the respective ends of the wallforming panels. The yadhesive coating applied to a surface of each closure flap is bondable only to another of the closure flap adhesive coatings. The method in question comprises folding one wide closure liap at each end of the blank into overlying relation with the wall-forming panel to which said ap is connected whereby the adhesive coating of the folded flap is adjacent to the overlaid surface of the wall-forming panel. The method also includes the step of folding one wide wall-forming panel and a narrow wall-forming panel interconnected thereto into overlapping relation with respect to the remaining interconnected narrow and wide wall-forming panels whereby the folded wide closure flaps are sandwiched between the overlapping wall-forming panels. Thus premature bonding of the adhesive coatings prior to setting up of the container is avoided.

Background 0f the invention' Containers, frequently referred to in the trade as selfsealing containers, have become more and more widely accepted commercially because of the convenience to the packer of sealing the container subsequent to loading thereof without the need for additional adhesives, tapes, or staples or special tools for applying same.

Various containers of this general type have heretofore been produced; however, because of certain design characteristics, they -are beset with numerous shortcomings. One such shortcoming is the fact that the self-adhering material applied to the mating surfaces of the end closure flaps must be carefully applied in a predetermined mismatching pattern whereby, when the container is in a collapsed condition and/or several such collapsed containers are stacked one upon the other, the end closure llaps of each container will not adhere to one another or to the flaps of the adjacent containers. Frequently, to apply the adhesive in the predetermined pattern requires costly and complex equipment and the speed of applying such adhesive is relatively slow.

Furthermore, because the predetermined pattern requires careful mismatching of certain of the adhesive areas, the amount of adhesive applied to the mating surface of given closure flaps oftentimes has to be substantially reduced with the result that the adhesive bond between the mating surfaces of the aps is ineffective especially when the product carried within the container is relatively heavy and/or the loaded ycontainer is subjected to abusive handling. In view of this fact, therefore, certain self-sealing containers are incapable of meeting the rigid and established requirements of the uniform freight classification.

Summary of the invention Thus, it is an object of this invention to provide a method of folding a blank for a self-sealing type container, whereby the shortcomings above-noted have been readily avoided.

It is a further object of this invention to provide a blank for a self-sealing type container wherein the adhesive can be applied expeditiously and in a continuous and conventional manner to the mating surfaces of the end closure flaps during fabricating of the blank itself.

It is a still further object of this invention to provide a blank for a self-sealing type container wherein there is no sacrifice of the adhesive bond between the mating surfaces of the closure flaps when the container is set up, and there is no problem of the mating surfaces of the flaps becoming prematurely bonded to one -another when the blank is partially set up to form a collapsed condition.

Further and additional objects will appear from the description, accompanying drawing, and appended claims.

In accordance with one embodiment of this invention, a method is provided of folding a blank for a rectangular container into a collapsed condition. The blank in question includes wall-forming panels foldably interconnected, wide closure flaps foldably connected to a corresponding edge of alternate panels, and narrow closure flaps foldably connected to a corresponding edge of the remaining panels whereby the closure flaps, when folded, cooperate with one another to effect closing of one end of the rectangular container erected from the blank. The mating surfaces of the closure flaps are coated with a self-adhering material of which there are several well-known types in the industry. The method in question comprises folding one of the wide closure flaps into overlying relation with respect to the interior surface of the panel to which said one flap is connected, and then folding the wall-forming panels whereby said folded one closure tlap is sandwiched between the folded panels. The adjacent free edges of the end panels, subsequent to folding of the latter, are secured to one another by tape or by other well-known means to form the manufacturers glue seam.

Description For a more complete understanding of this invention reference should be made to the drawing wherein:

FIGURE 1 is a plan view of one form of a blank having self-adhering material applied to the mating surfaces of the colsure flaps.

FIG. 2 is similar to FIG. 1 but showing said blank subsequent to certain of the closure flaps being folded into overlying relation with respect to the respective wallforming panels.

FIG. 3 is similar to FIG. 2 but showing the blank subsequent to the wall-forming panels thereof being folded so as to sandwich the previously folded closure flaps therebetween.

FIG. 4 is a perspective view of the blank of FIG. 3 set up for loading.

Referring now to the drawing and more particularly to FIG. 1, a blank 10, of preferably double face corrugated breboard, is shown which is adapted, in this instance, to form a regular slotted (RSC) container, see FIG. 4. If desired, the blank 10 may be formed of other suitable sheet material (e.g., paperboard) used in forming cartons, containers, boxes, or the like.

The blank in the illustrated embodiment, comprises wide wall-forming panels 11 and 12 arranged in alternate, side by side relation with respect to narrow wall-forming panels 13 and 14. Foldably connected to opposite ends (top and bottom) of the panels are closure flaps 11a-b,

12a-b, 13a-b, and 14a-b. In the illustrated embodiment both the top and bottom closure flaps have self-adhering material 15 applied to the mating surfaces thereof. The coated mating surfaces of aps 11a-b and 12a-b in the illustrated embodiment are the interior surfaces thereof whereas the coated surfaces of flaps 13a-b and 14a-b are the outer, or reversed, surfaces thereof. The aforesaid disposition of the coated flap surfaces occurs when the wide tiaps 11a-b and 12a-b are adapted to overlie the narrow liaps 13a-b and 14a-b when the container ends are to be closed. In instances, however, where the narrow tiaps are to overlie the wide flaps, the coated mating surfaces of the closure flaps are reversed from that shown. In either case, the self-adhering material may be readily applied to the mating surfaces by conventional gluing equipment at the time the blank is being formed.

In the illustrated embodiment, it will be noted that the entire mating surface of each flap is coated, thus effecting a full adhesive bond between the closure tiaps when they are folded into closing condition. By having full adhesive bond between the closure iiaps, the rigid and established requirements of the uniform freight classification are readily met. The self-adhering material applied to the closure flaps is of such a character that it will adhere only to a surface which has been previously coated with the same material.

Subsequent to the self-adhering material being applied to the mating surfaces of the closure flaps, one of the wide tiaps 11a-b or 12a-b at each end of the blank is folded into overlying relation with respect to the panel 11 or 12 to which said flap is connected.

As noted in FIG. 3, panel 11 is then folded relative to panel 13 so as to overlie same and in a like manner panel 14 is folded relative to panel 12, whereupon the adjacent free edges of panels 11 and 14 form a manufacturers joint and are joined by a suitable tape 16. In lieu of tape 16, either panel 11 or 14 may be provided with a conventional flap, not shown, which may be glued, stitched, or stapled to the other end panel so as to form the manufacturers joint. The blank, when folded to the position shown in FIG. 3, forms a collapsed tubular member T. The blank, when in condition T, is suitable for stacking with other blanks folded in a like manner for either bulk shipment to or bulk storage by the customer.

To effect erection of the container from condition T to condition E, the latter shown in FIG. 4, the collapsed tubular member is grasped at opposite edges A and B and compressive force is exterted thereon, whereupon the panels 11-14 will assume the squared up relation as seen in FIG. 4. Closure tiaps 11b-14b are then folded relative to one another so as to effect closing of the bottom end of the container. The container is then set upright whereby top-loading of the container can be accomplished. Where, however, side, or end, loading of the container is to be undertaken, the container with the squared up panels is arranged so that it rests upon one of the panels and initial closing of one end of the container may be delayed until the product has been spotted or located between the wall-forming panels.

A modied way of practicing the method in question would be to fold all of the wide closure tiaps 11a-b, and

12a-b into overlying relation with respect to the respective panels. It is intended that such a modification is included within the scope of the aforedescribed invention.

Thus, it will be seen that an improved method has been provided for pre-folding certain of the closure tiaps of a self-adhering type of container, whereby the adhesive does not have to be applied to the closure flaps in a predetermined complex and/ or exacting mismatching pattern, and yet the possibility of the closure flaps becoming accidentally bonded to themselves or to similar closure aps of a like container, when the container assumes a collapsed tu'bular form, have been readily avoided. Furthermore, there has been no sacrifice of bonding area between the closure flaps when practicing the improved method with the result that the containers are readily capable of meeting the rigid and established requirements of the uniform freight classification.

While several embodiments of this invention have been described above, further modications may be made thereto and it is contemplated, therefore, by the appended claims, to cover any such modifications as fall within the spirit and scope of this invention.

I claim:

1. A method of forming a collapsed tubular member from a blank of foldable sheet material, said blank having two pairs of wide and narrow rectangular wallforming panels alternately arranged and foldably interconnected, sets of wide and narrow closure flaps foldably connected to opposite ends of the respective wall-forming panels, and an adhesive coating applied to alternate surfaces of each set of closure aps, each closure flap adhesive coating being Ibondable only to another of the closure ap adhesive coatings; said method comprising folding at least one wide closure tiap of each set into overlying relation with the wall-forming panel to which said folded tiap is connected whereby the adhesive coating of said folded flap is adjacent the overlaid surface of the wall-forming panel, folding one wide panel and one narrow panel interconnected thereto into overlapping relation with respect to the remaining interconnected narrow and wide panels whereby the folded wide closure liaps are sandwiched between the overlapping wall-forming panels, and interconnecting the free edges of the end wall-forming panels of the blank to form the collapsed tubular member.

2. The method recited in claim 1 wherein the folded flaps, which are sandwiched between the overlapping panels, are foldably connected to opposite ends of the same wall-forming panel.

3. The method recited in claim 1 wherein all the wide closure flaps of each set are folded into overlying relation with respect to wide wall-forming panels and the folded wide closure flaps of both sets are sandwiched between the overlapping wall-forming panels.

References Cited UNITED STATES PATENTS 1,534,007 4/1925 Labombarde 93--56 3,055,152 9/ 1962 Williams 93-94 3,068,760 12/1962 Gross 93-49 WAYNE A. MORSE IR., Primary Examiner. 

